Why only Prothean.... i can think of Inusannon, Densorin even Leviathans.....

Krogan live for nearly 1500 years but i doubt they had the advanced technology to get to andromrda in the first place. You need a biiiig Eezo core for FTL, a way to discharge the drive in the void, or you travel stl, which would need plenty of tons of Deuterium to burn..... and it would take tousands of years this way. Remember the Krogan were pre space flight before the Salarians uplifted them.

But it would be quite strange if a former cycle would not have tried to reach Andromeda. Looking forward to it.

I doubt we will see the Insunnanon or Densorin even though it would be great to at least have a little bit on them.

As for the Leviathan I have a feeling they and the Remnant are as old as each other and likely butted heads before the Leviathans were near enough wiped out by the reapers.

And from what I can tell technology in the milky way has been stagnant for a long time due to the cycle as such it's possible the Krogan did have the tech from the Salarians. As we know they had ships during the Rachni war and the rebellions so it's possible but I don't think too likely due to them not having cryo and therefore they'd probably in fight and kill each other. If they didn't though it's been about what 800 years before the mass effect trilogy takes place since the Krogan rebellion started so they would have a 200 year then add the 600 years to travel for the andromeda they could have been there for 800 years already but I doubt it if I'm honest.

I agree, they would need to create these Species just for this ocasion.

I also agree that there is a certain stagnation regarding tech improvement due to the structure of the cycle and that the Reapers surely do not want the Cycles to become too advanced, as this would hamper the harvest.

Every species that is more advanced then stoneage will be harvested, as they would have much more time to develop on ME Tech then anyone else otherwise (looking at you, Protheans and Relay Tech).

They had the Basic ME Tech back at the Rachni War, something Humanity alone had up until Shanxi, well except the Asari. But the technology we use to keep an FTL drive operational, non stop, for 600 years, that has just been discovered recently. Without the ODSY technology you need to discharge the Core on a Planet or Planetoid, otherwise it would melt the Ship.

And think of the Food and Water supply if the are not in Cryo..... huge masses of it would be necessary, as we are talking about hundreds of years to keep the crew alive.

Otherwise there would already be a bunch of Asari, Krogan, Salarian and Turian Colonies in Andromeda, rendering the Initiative effectively useless, as it is a Multi-Species first time endeavour.

It 's like :

Humans ' Dear Council, we have an Idea of all Species trekking to Andromeda to build Colonies there.'

But it would be strange, if they were able to reverse engineer Sovereigns FTL Drive and create something new within 2 years... but you mentioned the Thanix Missiles/Guns and they originate from Sovereigns remains.

Why couldn't they increase the FTL speed aswell, as Reapers are supposed to travel at 30 ly/d, while we, and the Normandy, and the Tempest, and the Nexus and the Ark and actually everyone else in the Milky Way can only travel at around 12 ly/day (2.500.000 ly / 600 y / 365 d = 11,42 ly/d).

Reverse engineering is often not as good as the initial work due in part to the technology not being quite as understood by the people reverse engineering it and then take into account the 2 years they had to do it which would be remarkable considering how advanced the reapers are over everyone in the Milky Way technologically.

Also they would have to make several drives so the Nexus, 4 Arcs and then any other ships that have the upgraded drives and then with the risk of indoctrination if they used actual reaper parts.

All of this would result in less efficient drives due to being unable to use the original technology and the materials would probably have been lower quality than what the reaper drivers are made from.

The problem with Sovereign's remains is, that it was kept locked away by the Government and became classified. The AI is not governmental nor would it normally have access to these kind of information/technology, except, well except the Council supports the AI as a back up survival plan out of fear from the Reaper Threat which they are constantly denying up until it is too late.

No, no, too much variables, continue thinking about it would be.... problematic.